Applied Separations Inc. proposes to develop a competitively priced liquid CO2 flash chromatography system that will rapidly separate compounds with high resolution and significantly reduce organic solvent consumption. Pharmaceutical companies annually synthesize thousands of compounds in drug discovery laboratories in an attempt to find new drug molecules for commercialization. Each of these synthesized compounds may require many reaction and purification steps for further testing. The primary technique used in the pharmaceutical industry to purify these compounds is flash chromatography and it is preferred because of high sample loading capacity and ease of use. Unfortunately, existing flash chromatography instrumentation suffers from poor peak resolution and uses large volumes of organic solvents as the mobile phase in the separation. Within medicinal chemistry laboratories, flash chromatography is the main source of chemical waste. Applied Separations developed a Phase I prototype liquid CO2 flash chromatography system that successfully used liquid CO2 as a replacement for non polar organic solvent mobile phases. The instrument rapidly separated test compounds with increased compound resolution, significant solvent reduction and good compound recoveries. The specific aims of this Phase II proposal are to: (1) redesign the instrument based on the evaluation of the prototype and optimize the instrument components for reliability, serviceability, and assembly. (2) redesign software to improve usability including the computer interface and the integration of the solvent pump and CO2 software modules. (3) develop proprietary cartridges and vessels that are hand tightened and easy to use with superior chromatography. (4) Finally, construct two optimized liquid flash chromatographs for beta testing at biotechnology and drug discovery laboratories before the final design is locked.